On-The-Spot Imaging and Processing

The FLoid® Cell Imaging Station

The FLoid® Cell Imaging Station is the ideal instrument for the wide array of fluorescence imaging experiments that researchers are performing every single day. From checking GFP expression in a tissue culture facility or screening fluorescent samples prior to analysis on a high-end confocal microscope or flow cytometer, to teaching students the wonders of cell biology in an instructional lab, the FLoid® Cell Imaging Station makes the capture of two- and three-color fluorescence images as easy as taking pictures on a smartphone. Even the most novice users of fluorescence microscopy techniques can follow the intuitive icons on the user interface and capture publication-quality images in a matter of minutes right at their benchtop. By eliminating the inherent complexities of capturing and processing multicolor fluorescent cell images, the FLoid® Cell Imaging Station allows researchers to spend their time analyzing data and designing their next experiments, rather than worrying about the operation of a microscope.

Cell Imaging Where You Need It

Traditionally, researchers have been confined to small darkrooms to collect their fluorescence images—tucked away from the labs where their experiments are conducted. Even a quick check of their fluorescent samples to assess staining or GFP expression can be inordinately inconvenient.

In contrast, the FLoid® Cell Imaging Station blocks ambient light from interfering with the collection of fluorescence images, allowing the instrument to be placed on the laboratory bench, in a cell culture facility, or in a tissue culture hood. The open stage of the FLoid® instrument creates a workspace compatible with a variety of cell culture vessels. Cells grown on or in chamber slides, tissue culture dishes, multiwell plates, or even large culture flasks can be easily imaged using the FLoid® Cell Imaging Station (Figure 1, Figure 2). Moreover, the instrument stage is on a grease plate, allowing subtle and precise movement of the cell culture vessel (4 mm in each direction) once it is initially positioned on the stage.

Figure 1. Imaging immunofluorescence in the rat retina using the FLoid® Cell Imaging Station. Rat retinal tissue was fixed and stained for cholinergic amacrine cells using polyclonal goat anti–choline acetyltransferase antibody followed by Alexa Fluor® 488 anti–goat IgG antibody (green), and counterstained with DAPI (blue). The amacrine cells are seen in the inner nuclear layer of the retina; some displaced amacrine cells are also seen in the ganglion cell layer. Image was captured using the FLoid® Cell Imaging Station and reproduced with permission from Ulla Hasselrot, University of Louisville, Kentucky.

One of the most difficult aspects of fluorescent cell imaging is simply finding your cells of interest. Often researchers focus on a focal plane where they think they will find their cells, only to find that they are focusing on debris on top of the coverslip. To remedy this problem, a Focus Assist gauge on the FLoid® Cell Imaging Station represents the relative position of the objective during focusing. Each cell culture vessel has a specific focal plane; cells on a slide will be located between 1 and 2 on the Focus Assist scale, whereas cells in a T-75 flask will be found between 6 and 7. Once you have established the focal plane for your typical cell culture vessel, the Focus Assist gauge helps you to quickly focus on your cells in each new experiment, allowing you to easily find the focal plane where cells reside.

Once the cells are in focus, intuitive icons are used to turn on and off the bright-field and fluorescent (blue, green, or red) light sources. The brightness of the image is controlled by a single slider bar that controls gain, exposure time, and LED light intensity. Once you are happy with the focus and light intensity, a simple click of the camera icon captures the image of interest.

Fluorescence imaging with traditional microscopes often requires that researchers import their individual files into third-party software programs such as Adobe Photoshop® or Image J to overlay the different fluorescence images that have been collected. With the FLoid® Cell Imaging Station, overlaying images is as easy as clicking the processing tab. Once on the processing tab, the brightness and contrast of images taken from each fluorescence channel can be adjusted using the slider bars. If you prefer to remove a particular color from the image, simply toggle off the color to remove it from the overlay. The numerical values associated with light intensity, brightness, and contrast are consistent each time you use the FLoid® instrument, which means that you can compare changes in fluorescence intensity of your cells over time by using the same settings.

With the digital zoom set at 200%, the magnification is equivalent to that of a 40x optical objective (Figure 3). The digital zoom can be set as high as 400%, producing an image with a total magnification of 1,840x and equivalent to an 80x objective. Because the FLoid® Cell Imaging Station uses a high-quality 20x objective and a highly sensitive CCD camera, the resolution of the captured images is still excellent at these increased digital magnifications.

For years, researchers have experienced the convenience of printing pictures of their gels for their lab notebooks from gel documentation stations. The FLoid® Cell imaging Station brings the convenience of data documentation to fluorescent cell imaging. The associated printer creates a credit card–sized, adhesive-backed print of your captured image that can be placed directly into a laboratory notebook.

Figure 3. Zooming in with the FLoid® Cell Imaging Station. The FLoid® Cell Imaging Station is equipped with a high-quality 20x fluorite objective. Additional magnification of an image can be achieved using the digital zoom in the image processing tab. Setting the digital zoom at 200% gives magnification equivalent to that of a 40x objective. Here we show four screen captures of an image following digital magnification on the FLoid® Cell Imaging Station.

The steep learning curves of many large and expensive fluorescence microscopes have kept many researchers from utilizing fluorescence microscopy in their research. With the FLoid® Cell Imaging Station, even students and novice researchers can easily capture and then process an image with a few clicks of the mouse.

View From the Lab

For the better part of a year, Ulla Hasselrot has been using the FLoid® Cell Imaging Station in the lab where she conducts her research in the Department of Anatomical Sciences and Neurobiology at the University of Louisville, Kentucky. She is part of a research team studying the plasticity of the nervous system, with the long-range goal of understanding neurodegenerative pathways from stimulus to cell death. Specifically, she is using immunofluorescence to detect proteins overexpressed when the retina is exposed to ischemic conditions.

“Do you want to see a picture?” Ulla asks, as she explains how the FLoid® Cell Imaging Station has enhanced her ability to share her work with the rest of the group during trouble-shooting sessions and lab meetings. She can call up the images in a snap and then simply turn off the instrument when the show-and-tell is over; there’s no waiting around for bulbs to cool off. She also tells us that her workday is much easier now that she has “access to an imaging system in my own lab that I can use whenever I like and for as long as I like.” And she has found that the FLoid® image quality is so good that she typically can’t tell whether a particular image is from the FLoid® instrument or the expensive microscope upstairs. In Ulla’s words, “FLoid® does the job, does it fast, and gives really really nice results.”